Buggy code:
public class GetServerMessages { public static String newestreply = null ; public static void CheckServerMessages ( String FullMsg ) { GetServerMessages . newestreply = FullMsg ; String [ ] Args = FullMsg . split ( "<seq2seq4repair_space>" ) ; if ( Args [ 0 ] . equals ( ".System" ) ) { Platform . runLater ( new Runnable ( ) { @ Override public void run ( ) { Main . AddToMessageField ( FullMsg . replace ( ".System" , "" ) , 2 ) ; } } ) ; } else if ( Args [ 0 ] . equals ( ".connect" ) ) { Platform . runLater ( new Runnable ( ) { @ Override public void run ( ) { if ( ! ( names . contains ( Args [ 1 ] ) ) ) { names . add ( Args [ 1 ] ) ; } if ( ! ( UserTable . contains ( Args [ 1 ] ) ) ) { UserTable . put ( Args [ 1 ] , "User" ) ; } Main . AddToMessageField ( ( ( ".System<seq2seq4repair_space>" + ( Args [ 1 ] ) ) + "<seq2seq4repair_space>connected." ) , 2 ) ; if ( ! ( primstage . isFocused ( ) ) ) { primstage . getIcons ( ) . add ( new Image ( "orange.png" ) ) ; } } } ) ; } else if ( Args [ 0 ] . equals ( ".disconnect" ) ) { Platform . runLater ( new Runnable ( ) { @ Override public void run ( ) { if ( names . contains ( Args [ 1 ] ) ) { names . remove ( Args [ 1 ] ) ; } if ( UserTable . contains ( Args [ 1 ] ) ) { UserTable . remove ( Args [ 1 ] ) ; } Main . AddToMessageField ( ( ( ".System<seq2seq4repair_space>" + ( Args [ 1 ] ) ) + "<seq2seq4repair_space>disconnected." ) , 2 ) ; } } ) ; } else if ( Args [ 0 ] . equals ( ".namechange" ) ) { Platform . runLater ( new Runnable ( ) { @ Override public void run ( ) { if ( names . contains ( Args [ 1 ] ) ) { names . remove ( Args [ 1 ] ) ; names . add ( Args [ 2 ] ) ; } else { names . add ( Args [ 2 ] ) ; } if ( UserTable . contains ( Args [ 1 ] ) ) { UserTable . remove ( Args [ 1 ] ) ; UserTable . put ( Args [ 2 ] , "User" ) ; } else { UserTable . put ( Args [ 2 ] , "User" ) ; } Main . AddToMessageField ( ( ( ( ( ".System<seq2seq4repair_space>" + ( Args [ 1 ] ) ) + "<seq2seq4repair_space>changed<seq2seq4repair_space>name<seq2seq4repair_space>to<seq2seq4repair_space>" ) + ( Args [ 2 ] ) ) + "." ) , 2 ) ; } } ) ; } else if ( Args [ 0 ] . equals ( ".confirmAdmin" ) ) { Main . ActiveUsername = "." + ( Main . ActiveUsername ) ; } else if ( Args [ 0 ] . equals ( ".ACA" ) ) { Platform . runLater ( new Runnable ( ) { @ Override public void run ( ) { console . setText ( "" ) ; <START_BUG> content . getChildren ( ) . clear ( ) ; <END_BUG> TextInputField . clear ( ) ; } } ) ; } else if ( Crypter . decrypt ( Crypter . decrypt ( Crypter . decrypt ( Crypter . decrypt ( FullMsg , 0 ) , 1 ) , 2 ) , 3 ) . startsWith ( "text" ) ) { String entrymsg = Crypter . decrypt ( Crypter . decrypt ( Crypter . decrypt ( Crypter . decrypt ( FullMsg , 0 ) , 1 ) , 2 ) , 3 ) ; Platform . runLater ( new Runnable ( ) { @ Override public void run ( ) { if ( Main . RemoveFromMessageField ( entrymsg ) ) { if ( StyleChooser . isSelected ( ) ) { Main . AddToMessageField ( entrymsg . replace ( "text<seq2seq4repair_space>" , "" ) , 1 ) ; } else { String temp21 = entrymsg . substring ( 5 , entrymsg . length ( ) ) ; String Sender = temp21 . substring ( 1 , temp21 . indexOf ( "]" ) ) ; String text = temp21 . substring ( ( ( temp21 . indexOf ( "]" ) ) + 4 ) , temp21 . length ( ) ) ; Main . AlternativeAddToMessageField ( text , 0 , Sender ) ; } if ( ! ( primstage . isFocused ( ) ) ) { primstage . getIcons ( ) . add ( new Image ( "orange.png" ) ) ; } } } } ) ; } else { } } }

Fix:
Main . ClearMsgField ( ) ;